The Herschel Extragalactic Legacy Project (HELP) brings together a vast range of data from many astronomical observatories. Its main focus is on the Herschel data, which maps dustobscured star formation over 1300 deg2. With this unprecedented combination of data sets, it is possible to investigate how the star formation versus stellar mass relation (main sequence) of star-forming galaxies depen...

We re-examine critically the estimates of the duration of different phases of star formation and the lifetimes of molecular clouds, based on the ages of T-Tauri stars, age spreads of stars in clusters, and statistics of pre-stellar cores. We show that all available observational data are consistent with lifetimes of molecular clouds comparable to ≈ 10 yr, as well as with the predictions of the ...

The extraordinary starbursts found in ultraluminous IR galaxies occur in molecular gas concentrated in compact very massive “clouds” which we call “Extreme Starbursts”. They have one thousand times the mass but are only a few times larger than GMCs. High-mass star formation in sufficiently dense and massive structures does not disrupt further star formation; it is a runaway process. Star format...

In the past decade filaments have been recognised as a major structural element of interstellar medium, densest these hosting formation most stars. some star-forming molecular clouds converging networks filaments, also known hub filament systems, can be found. These hubs are believed to preferentially associated massive star formation. As today, there no metrics that allow systematic quantifica...

• One of the most important processes for galaxy formation and evolution ! • Big questions! – When and how does star formation occur ?! – How is it related to the evolution of galaxy properties?! – What are the physical processes that drive star formation ?! • star formation occurs (at least in spirals at low z) almost exclusively associated with molecular clouds! – what is the rate at which st...

We place constraints on the formation redshifts for blue globular clusters (BGCs), independent of the details of hydrodynamics and population III star formation. We argue that BGCs and stellar halos have a common origin and that simulations of 1 Mpc boxes up to z ∼ 10 must resolve BGC formation. We present a proof-of-concept simulation that captures the formation of globular-like star clusters....

We simulate the formation and evolution of galaxies with a self-consistent 3D hydrodynamical model including star formation, supernova feedback, and chemical enrichment. Hypernova feedback plays an essential role not only in solving the [Zn/Fe] problem, but also reproducing the cosmic star formation rate history and the mass-metallicity relations. In a MilkyWay type galaxy, kinematics and chemi...

Nuclear star clusters (NSCs) are massive found in all types of galaxies from dwarfs to galaxies. Recent studies show that while low-mass NSCs dwarf ($M_\text{gal} < 10^{9} M_\odot$) form predominantly out the merger globular (GCs), high-mass have assembled most their mass through central enriched formation. So far, these results a transition dominant NSC formation channel been based on early-ty...

With the imagery from GALEX, HST, 2MASS, and Spitzer, and at the resolution of MIPS 24 μm (∼ 6), we study the variations of the broadband spectral energy distributions (SEDs) of star-forming regions within the nearest prototypal major merger — the Antennae galaxies. By including MIPS 24μm dust emission into stellar population analysis, we reliably, albeit roughly, constrain the star formation h...

The star formation history of the northern and southern M31 disk is measured using samples of BV photometry for 4’ × 4’ regions taken from the KPNO/CTIO Local Group Survey (Massey et al. 2001). The distances, mean reddening values, and age distributions of the stars in these regions were measured using the routines of Dolphin (1997, 2002). Independent measurements of overlapping fields show tha...